In recent years, image pick-up apparatuses using solid-state image pick-up devices such as digital still camera, etc. are being popularized. Especially, with popularization of digital still camera, there is required a zoom lens having excellent compactness and having high image formation performance in the entire zooming range irrespective of object distance while covering the range from the broad angle side up to the telescopic side.
For example, in zoom lenses described in the Japanese Patent Application Laid Open No. 1992-146407 publication and the Japanese Patent Application Laid Open No. 1999-174324 publication, six lens groups consisting of positive lenses, negative lenses, positive lenses, negative lenses, positive lenses and negative lenses are provided to perform realization of high magnification changing or adjusting operation.
However, the zoom lenses described in the Japanese Patent Application Laid Open No. 1992-146407 publication and the Japanese Patent Application Laid Open No. 1999-174324 publication relate to exchange lens of single-lens reflex camera, etc., and are difficult in miniaturization and realization of broad angle because long back-focus for arrangement space of mirror for jumping up mirror, etc. must be ensured.
In view of the problems as described above, an object of the present invention is to provide a zoom lens system, compact and having high image formation performance over the entire zooming lens area irrespective of object lens while covering the range from the broad angle side up to the telescopic side, which is used in video camera and/or digital still camera; and an image pick-up apparatus using such a zoom lens system.